SanDisk was one of three companies to develop and market the SD (secure digital?) in 1999. 14 years later (2013), SanDisk has gone from a 1GB CF card to a 128GB SD - quite the progress. The 128GB capacity is has been regarded very highly as RAW file sizes, as well as HD Video Capture, writes in larger and larger as image sensors continue to improve noise levels to ultra-high ISOs. This card retails on Amazon for $136 (at time of posting) and is advertised with a 45MB/sec throughput.

First Impressions:

Does it hit 45MB/sec? No

What's the actual formatted capacity? 128.83GB.

Is it the fastest SD card on the market? No, the Extreme Pro line is, but that line doesn't hit the 128GB capacity range.

ConclusionsFor still shooters, the SanDisk Extreme 128GB SD card is now the last card you'll probably need for the next 3-5 years. If you shoot 30MB RAW files, you can shoot 4,369 RAW images until this card becomes full. If your RAW images are 50MB each, you'll max this one at 2,621 images. 80% of cameras fall under 30MB per RAW file. For video shooters, multiple 30-minute clips can be shot in sequence with just a short break in-between.

Wether you're going to be shooting stills or video, get the SanDisk Extreme 128GB over the Transcend 128GB SD TS128GS. It's only $30 more . For any capacities lower than 128GB, I recommend the Transcend as the price point as it's much less expensive and the speed/reliability is excellent.

Another use-case which is relevant to add here (for Mac users) is to reformat this card to HFS+ Encrypted and use it as a removable storage space. Very convenient for backing up image databases, wether they be SQL-based or Aperture Vault-based, or just plain Time-Machine backups : )